<!DOCTYPE html>
<html>

<head>
    <meta charset="UTF-8" />
    <title>2_原生事件绑定</title>
    <script type="text/javascript" src="../js/vue.js"></script>
</head>

<body>
    <button id="btn1">按钮1</button>
    <button id="btn2">按钮2</button>
    <button id="btn3" onclick="demo()">按钮3</button>
    <script type="text/javascript">
        const btn1 = document.getElementById('btn1');
        btn1.addEventListener('click', () => {
            alert('按钮1被点击了')
        })
        const btn2 = document.getElementById('btn2');
        btn2.onclick = () => {
            alert('按钮2被点击了')
        }

        function demo() {
            alert('按钮3被点击了')
        }
    </script>
</body>

</html>